This invention relates to contraceptives and, more particularly, to a female contraceptive.
The most common type of female contraceptive is the diaphragm. A diaphragm is a device usually made of thin, flexible material which is placed in the vaginal vault for blocking the entrance to the cervix in order to prevent impregnation during sexual intercourse. Generally, such diaphragms comprise a loose hanging pouch made of an elastomeric material such as rubber formed with an integral, heavy, resilient rim intended to engage the walls of the vaginal vault. In order to prevent the intrusion of spermatozoa or disease-carrying organisms into the cervix, a diaphragm is most usually used in combination with a spermicidal cream. The combination of the two--diaphragm and the spermicidal cream--usually makes a cumbersome and inconvenient contraceptive.
Over the years, a number of improvements in contraceptives have been suggested. Thus, for example, J. T. Clark, in U.S. Pat. Nos. 2,463,356; 2,540,932; and 2,638,896; as well as Ballard et al., in U.S. Pat. No. 2,529,363; Snell, in U.S. Pat. Nos. 2,538,478; and 3,117,573; Young, in U.S. Pat. No. 2,625,154; Kunnas, Jr., in U.S. Pat. No. 2,823,669; Milgrom et al., in U.S. Pat. No. 3,036,570; Lay, in U.S. Pat. No. 2,249,316; and Duncan, in U.S. Pat. No. 3,545,439 all suggest spring-loaded diaphragm rims for resiliently collapsing the diaphragm for ease of insertion and the subsequent firm engagement of the walls of the vaginal vault.
The disadvantage of these devices is that the prophylactic effect is achieved by sealing the diaphragm at the vaginal wall. Pressure can, in some instances, result in discomfort. Insufficient pressure can result in either impregnation and/or disease entering the cervix.
Another approach was suggested by Harris in U.S. Pat. No. 2,522,822, in which a disposable vaginal diaphragm or pessary is suggested. Essentially, Harris suggests the use of a soft and pliable contraceptive. However, it is believed that such a device cannot be held securely in place within the vaginal vault, thereby causing great difficulty and possible misplacement during sexual intercourse.
Sponges or sponge-like devices have been suggested in the form of pessaries, as disclosed by Steiger et al., in U.S. Pat. No. 3,216,422; Young, in U.S. Pat. No. 3,128,762; and Cruickshank, in U.S. Pat. No. 2,020,107. In the device disclosed by Steiger et al., the sponge hangs loosely from an impervious film. The other sponge-like devices are either intended to engage the cervix in a glove-like arrangement or in a cup-like arrangement, similar in shape to prior art diaphragms. The spacing from the cervix opening of cup-like devices increases the possibility of impregnation or infection. The glove-like devices are believed to be difficult to insert and must be specially fitted to each individual user. Thus, these devices have the same disadvantages as other rim-securing diaphragm devices.
The above-referenced devices are representative of the wide variety of constructions, each having in common the fact that either the rim of the diaphragm is spring-loaded to form a specific contact and that the sealing characteristics are being provided by the rim, or a sponge-like material, which is loosely folded as such, the latter having the difficulty of being easily misplaced or mislocated in insertion.